BACKGROUND: KRAS-mutant lung adenocarcinomas (LUADs) are heterogeneous and frequently occur in smokers. The heterogeneity of KRAS-mutant LUAD has been an obstacle for the drug discovery.
METHODS: We integrated multiplatform datatypes and identified two corresponding subtypes in the patients and cell lines. We further characterized the features of these two subtypes and performed drug screening to identify subtype-specific drugs. Finally, we used the defining features of the KRAS subtypes for drug sensitivity prediction.
FINDINGS: Patient-Subtype 1 (PS1) was characterized by increased smoking-related mutational signature activity, a low tumor-infiltrating lymphocyte (TIL)-associating score and STK11/KEAP1 co-mutations. Patient-Subtype 2 (PS2) was characterized by an increased smoking-related methylation signature activity, a high TIL-associating score and increased KRAS dependency. The cell line subtypes faithfully recapitulated all the patients' features. Drug screening of the two cell line subtypes yielded several potential candidates, such as cytarabine and enzastaurin for Cell-line-Subtype 1 (CS1) and a BTK inhibitor QL-XII-61 for Cell-line-Subtype 2 (CS2). The defining features, such as smoking-related methylation signature, were significantly associated with the sensitivity to several drugs.
INTERPRETATION: The heterogeneity of KRAS-mutant LUAD is associated with smoking-related genomic and epigenomic aberration along with other features such as immunogenicity, KRAS dependency and STK11/KEAP1 co-mutations. These features might be used as biomarkers for drug sensitivity prediction. FUND: This research was funded by the Young Scientists Fund of the National Natural Science Foundation of China, the Natural Science Foundation of Fujian Province, China and the Education and Research Foundation for Young Scholars of Education Department of Fujian Province, China.

BACKGROUND: Alzheimer's disease (AD) is a neurodegenerative disease that is clinically characterized by progressive cognitive decline. Mutations in amyloid-β precursor protein (APP), presenilin 1 (PSEN1), and presenilin 2 (PSEN2) are the pathogenic cause of autosomal dominant AD (ADAD). However, polymorphisms also exist within these genes.
METHODS: In order to distinguish polymorphisms from pathogenic mutations, the DIAN Expanded Registry has implemented an algorithm for determining ADAD pathogenicity using available information from multiple domains, including genetic, bioinformatic, clinical, imaging, and biofluid measures and in vitro analyses.
RESULTS: We propose that PSEN1 M84V, PSEN1 A396T, PSEN2 R284G, and APP T719N are likely pathogenic mutations, whereas PSEN1 c.379_382delXXXXinsG and PSEN2 L238F have uncertain pathogenicity.
CONCLUSIONS: In defining a subset of these variants as pathogenic, individuals from these families can now be enrolled in observational and clinical trials. This study outlines a critical approach for translating genetic data into meaningful clinical outcomes.

AIB1 was involved in the development and progression of breast cancer. Although it was found that AIB1 could be phosphorylated by some kinases including PI3K, the function of AIB1 and AKT interaction in breast cancer is not well defined. MCF-7 cells were transfected with pERE-Luc AKT and/or AIB1 plasmids, and then ERE luciferase activity in presence or absence of estrogen (E2) were measured. Plasmids containing PTEN and an PI3K inhibitor LY294002 were transfected into or treated cells to identify the interaction of PI3K/AKT and activation of AIB1, and examine their roles in cell cycle regulation. The AKT phosphorylation activity was evaluated by kinase assay using H2B as a substrate. The association between A1B1 and pS2 promoter was detected by the Chromatin Immunoprecipitation (ChIP) assay. AIB1 and AKT in the same complex were detected by Pull-down assay. IGF-1 can increase AIB1 recruitment to PS2 and enhance the ER-dependent transcription activity through the PI3K/AKT pathway. AIB1 associate with AKT to regulate cell cycle. The special relations concerning the AIB1 and AKT may arouse some new viewpoints for potential therapeutic targets in breast cancer.

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Trefoil Factor 1 (TFF1, also named pS2), which serves as the gastrointestinal mucosal protector, is known as gastric-specific tumor suppressor gene. However, the genetic variants of TFF1 are still not well studied. In our study, we aim to explore the effects of tagging single nucleotide polymorphisms (tagSNPs) of TFF1 on risk and prognosis of gastric cancer. Seven tagSNPs of TFF1 gene were first analyzed in the discovery set, which was consisted of 753 cases and 950 cancer-free controls. Then, the validation set (940 cases and 1,042 controls) was used for further evaluation. Moreover, we also tested the relation between these tagSNPs and prognosis of gastric cancer (GC). A series of experiments were performed to investigate the underlying mechanisms. We found that rs3761376 AA in the promoter region of TFF1, could reduce the expression of TFF1 by affecting the binding affinity of estrogen receptor 1 (ESR1, ERα), and thereby increased the risk of GC (1.29, 1.08-1.53). Moreover, the rs3761376 AA genotype was also found associated with worse prognosis among patients receiving 5-FU based chemotherapy after surgery (1.71, 1.18-2.48). Further functional assays demonstrated that TFF1 could increase the chemosensitivity of 5-FU by modulating NF-κB targeted genes. These results identified the effect of rs3761376 on TFF1 expression, which accounted for the correlation with susceptibility and prognosis of GC; and this genetic variant may be a potential biomarker to predict the risk and survival of GC.

Heat shock factor 4 (HSF4) is a member of the HSF family. In this study, by using data from the Cancer Genome Atlas-Colorectal Cancer (TCGA-CRC), we investigated the expression profile and the prognostic value of the HSF4 in terms of overall survival (OS) and recurrence free survival (RFS) in CRC patients. RNA-Seq data showed that HSF4 RNA expression was significantly higher in CRC tissues (N = 380) than in the corresponding normal tissues (N = 51) (mean ± SD: 3.56 ± 1.28 vs. 1.85 ± 0.87, P < 0.0001). High HSF4 expression group had significantly higher ratio of stages III/IV patients (52/86, 60.5%) than low HSF4 expression group (110/264, 41.7%; P = 0.0024). Besides, the high HSF4 expression group also had significantly increased expression of CEA (CEA ≥ 5, 26/51, 51.0% vs. 64/186, 34.4%), higher proportion of recurrence (32/86, 37.2% vs. 48/254, 18.9%, P = 0.0005) and death (36/90, 40.0% vs. 49/277, 17.7%, P < 0.0001) compared with the low HSF4 expression group. Multivariate analysis confirmed that high HSF4 expression was an independent prognostic factor of poor OS (HR = 2.111, 95%CI: 1.350-3.302, P = 0.001) and RFS (HR = 1.958, 95%CI: 1.224-3.131, P = 0.005). Bioinformatic analysis showed that HSF4 can directly interact with DUSP26, ZBED8, and MAPK14. It is also coexpressed with PTGER1, COL11A2, CLPS, and ARSA and colocalized with PTGER1, ADRB1, PEX12, CLPS, PSEN2, KCNJ5, CPA1, ARSA, PNLIP, IRX4, CPA2, IDUA, BCKDHA, and CTRL. We hypothesized that HSF4 might exert its oncogenic effects in CRC via some of these genes. © 2017 IUBMB Life, 69(12):956-961, 2017.

Some epidemiological studies suggest an inverse correlation between cancer incidence and Alzheimer's disease (AD). In this study, we demonstrated experimental evidences for this inverse relationship. In the co-expression network analysis using the microarray data and GEO profile of gene expression omnibus data analysis, we showed that the expression of peroxiredoxin 6 (PRDX6), a tumor promoting protein was significantly increased in human squamous lung cancer, but decreased in mutant presenilin 2 (PS2) containing AD patient. We also found in animal model that mutant PS2 transgenic mice displayed a reduced incidence of spontaneous and carcinogen-induced lung tumor development compared to wildtype transgenic mice. Agreed with network and GEO profile study, we also revealed that significantly reduced expression of PRDX6 and activity of iPLA2 in these animal models. PS2 mutations increased their interaction with PRDX6, thereby increasing iPLA2 cleavage via increased γ-secretase leading to loss of PRDX6 activity. However, knockdown or inhibition of γ-secretase abolished the inhibitory effect of mutant PSs. Moreover, PS2 mutant skin fibroblasts derived from patients with AD showed diminished iPLA2 activity by the elevated γ-secretase activity. Thus, the present data suggest that PS2 mutations suppress lung tumor development by inhibiting the iPLA2 activity of PRDX6 via a γ-secretase cleavage mechanism and may explain the inverse relationship between cancer and AD incidence.

The processing of the amyloid-β protein precursor (AβPP) by β- and γ-secretases is a pivotal event in the genesis of Alzheimer's disease (AD). Besides familial mutations on the AβPP gene, or upon its overexpression, familial forms of AD are often caused by mutations or deletions in presenilin 1 (PSEN1) and 2 (PSEN2) genes: the catalytic components of the proteolytic enzyme γ-secretase (GS). The "amyloid hypothesis", modified over time, states that the aberrant processing of AβPP by GS induces the formation of specific neurotoxic soluble amyloid-β (Aβ) peptides which, in turn, cause neurodegeneration. This theory, however, has recently evidenced significant limitations and, in particular, the following issues are debated: 1) the concept and significance of presenilin's "gain of function" versus "loss of function"; and 2) the presence of several and various GS substrates, which interact with AβPP and may influence Aβ formation. The latter consideration is suggestive: despite the increasing number of GS substrates so far identified, their reciprocal interaction with AβPP itself, even in the AD field, is significantly unexplored. On the other hand, GS is also an important pharmacological target in the cancer field; inhibitors or GS activity are investigated in clinical trials for treating different tumors. Furthermore, the function of AβPP and PSENs in brain development and in neuronal migration is well known. In this review, we focused on a specific subset of GS substrates that directly interact with AβPP and are involved in its proteolysis and signaling, by evaluating their role in neurodegeneration and in cell motility or proliferation, as a possible connection between AD and cancer.

BACKGROUND: The androgen receptor (AR) is the classical target for prostate cancer prevention and treatment, but more recently estrogens and their receptors have also been implicated in prostate cancer development and tumor progression.
METHODS: Recent experimental and clinical data were reviewed to elucidate pathogenetic mechanisms how estrogens and their receptors may affect prostate carcinogenesis and tumor progression.
RESULTS: The estrogen receptor beta (ERβ) is the most prevalent ER in the human prostate, while the estrogen receptor alpha (ERα) is restricted to basal cells of the prostatic epithelium and stromal cells. In high grade prostatic intraepithelial neoplasia (HGPIN), the ERα is up-regulated and most likely mediates carcinogenic effects of estradiol as demonstrated in animal models. The partial loss of the ERβ in HGPIN indicates that the ERβ acts as a tumor suppressor. The tumor promoting function of the TMPRSS2-ERG fusion, a major driver of prostate carcinogenesis, is triggered by the ERα and repressed by the ERβ. The ERβ is generally retained in hormone naïve and metastatic prostate cancer, but is partially lost in castration resistant disease. The progressive emergence of the ERα and ERα-regulated genes (eg, progesterone receptor (PR), PS2, TMPRSS2-ERG fusion, and NEAT1) during prostate cancer progression and hormone refractory disease suggests that these tumors can bypass the AR by using estrogens and progestins for their growth. In addition, nongenomic estrogen signaling pathways mediated by orphan receptors (eg, GPR30 and ERRα) has also been implicated in prostate cancer progression.
CONCLUSIONS: Increasing evidences demonstrate that local estrogen signaling mechanisms are required for prostate carcinogenesis and tumor progression. Despite the recent progress in this research topic, the translation of the current information into potential therapeutic applications remains highly challenging and clearly warrants further investigation.

In this study the effect of silver nanoparticles (AgNPs) on proliferation of estrogen receptor (ER)-positive human breast cancer MCF-7/BUS cells was assessed by means of in vitro assay. The cells were exposed in the absence of estrogens to AgNPs alone or in combination with aluminum chloride (AlCl

OBJECTIVES: Trefoil Factor Family protein 1 (TFF1) is secreted from mucus-producing cells. The relationship between TFF1 expression and clinical outcome in pancreatic ductal adenocarcinoma (PDAC) remains unknown. We aimed to evaluate the prognostic significance of TFF1 expression in PDAC.
METHODS: TFF1 expression was examined on paraffin-embedded sections from 91 patients with resected PDAC using immunohistochemistry. The relationships between TFF1 expression and clinicopathological features were analyzed.
RESULTS: Among 91 PDAC patients, 71 patients (79.7%) showed TFF1 expression in cancer cells. In a subgroup of 71 patients, TFF1 expression was predominantly observed in the central part of the tumor, whereas TFF1 expression in the invasion front was reduced in 33 patients (46.4%). A significant correlation between preserved TFF1 expression in the invasion front and lymph node metastasis was observed. Univariate survival analysis revealed that preserved TFF1 expression in the invasion front, positive lymphatic invasion, lymph node metastasis and R1 resection was a significant poor prognostic factor in TFF1-positive PDAC patients.
CONCLUSIONS: TFF1 expression is frequently lost or decreased in the invasion front of human PDAC, and preserved TFF1 expression in the invasion front might predict poor survival in patients with PDAC.

Unlike breast cancer that is positive for estrogen receptor-α (ERα), there are no targeted therapies for triple-negative breast cancer (TNBC). ERα is silenced in TNBC through epigenetic changes including DNA methylation and histone acetylation. Restoring ERα expression in TNBC may sensitize patients to endocrine therapy. Expression of c-Src and ERα are inversely correlated in breast cancer suggesting that c-Src inhibition may lead to reexpression of ERα in TNBC. KX-01 is a peptide substrate-targeted Src/pretubulin inhibitor in clinical trials for solid tumors. KX-01 (1 mg/kg body weight-twice daily) inhibited growth of tamoxifen-resistant MDA-MB-231 and MDA-MB-157 TNBC xenografts in nude mice that was correlated with Src kinase inhibition. KX-01 also increased ERα mRNA and protein, as well as increased the ERα targets progesterone receptor (PR), pS2 (TFF1), cyclin D1 (CCND1), and c-myc (MYC) in MDA-MB-231 and MDA-MB-468, but not MDA-MB-157 xenografts. MDA-MB-231 and MDA-MB-468 tumors exhibited reduction in mesenchymal markers (vimentin, β-catenin) and increase in epithelial marker (E-cadherin) suggesting mesenchymal-to-epithelial transition (MET). KX-01 sensitized MDA-MB-231 and MDA-MB-468 tumors to tamoxifen growth inhibition and tamoxifen repression of the ERα targets pS2, cyclin D1, and c-myc. Chromatin immunoprecipitation (ChIP) of the ERα promoter in KX-01-treated tumors demonstrated enrichment of active transcription marks (acetyl-H3, acetyl-H3Lys9), dissociation of HDAC1, and recruitment of RNA polymerase II. Methylation-specific PCR and bisulfite sequencing demonstrated no alteration in ERα promoter methylation by KX-01. These data demonstrate that in addition to Src kinase inhibition, peptidomimetic KX-01 restores ERα expression in TNBC through changes in histone acetylation that sensitize tumors to tamoxifen.

Unlike other breast cancer subtypes, targeted therapies for triple negative breast cancer (TNBC) have yet to progress past clinical trial stage to approval. Accumulating evidences demonstrated that expression of estrogen-related receptor alpha (ERRα) indicated worse prognosis and correlated with poor outcome in breast cancers including TNBC. Therefore, ERRα modulators/regulators may be potential in the therapeutic treatment of breast cancers. In the current study, we presented a novel compound LingH2-10 that bound to ERRα, as identified using a time-resolved fluorescence resonance energy transfer assay (TR-FRET) with the IC

Bisphenol A (BPA) is an endocrine disrupting compound used in food and beverage plastic containers and has been shown to increase breast cancer cellular proliferation. However, the concentrations of BPA used in these experiments are far higher than the physiological levels of BPA detected in the human body. We observed in vitro that exposure of MCF-7 cells to physiological concentrations of BPA failed to increase cell proliferation or to induce canonical estrogen-responsive genes (pS2 and progesterone receptor (PR)), in contrast to 17β-estradiol (E2) treatment. However, MCF-7 cells treated with 10 nM BPA induced ALDH1 expression, a marker of human mammary stem cells. When treated with 10 nM BPA, mammospheres derived either from MCF-7 cells, a patient-derived xenograft, or the normal mouse mammary gland exhibited increased size; however, these effects were not observed in MDA-MB-231 mammospheres. Mechanistically, BPA induced SOX2 mRNA and protein in MCF-7 mammospheres, resulting from enhanced CREB phosphorylation, and subsequent binding of pCREB to a SOX2 downstream enhancer. These findings suggest that physiological levels of BPA increase estrogen receptor-positive breast cancer tumor maintenance through enhanced cancer stem-like cell activity via direct regulation of SOX2 transcription.

Estrogens have been implicated as complete carcinogens for breast and other tissues through mechanisms involving increased cell proliferation, oxidative stress, and DNA damage. Because of their potent antioxidant activity and other effects, tocopherols have been shown to exert antitumor activities in various cancers. However, limited information is available on the effect of different forms of tocopherols in estrogen-mediated breast cancer. To address this, we examined the effects of α-, γ-, and δ-tocopherols as well as a natural γ-tocopherol-rich mixture of tocopherols, γ-TmT, on estrogen-stimulated MCF-7 cells

In the complex network of nuclear hormone receptors, the long non-coding RNAs (lncRNAs) are emerging as critical determinants of hormone action. Here we investigated the involvement of selected cancer-associated lncRNAs in Estrogen Receptor (ER) signaling. Prior studies by Chromatin Immunoprecipitation (ChIP) Sequencing showed that in prostate cancer cells ERs form a complex with the endothelial nitric oxide synthase (eNOS) and that in turn these complexes associate with chromatin in an estrogen-dependent fashion. Among these associations (peaks) we focused our attention on those proximal to the regulatory region of HOTAIR and MALAT1. These transcripts appeared regulated by estrogens and able to control ERs function by interacting with ERα/ERβ as indicated by RNA-ChIP. Further studies performed by ChIRP revealed that in unstimulated condition, HOTAIR and MALAT1 were present on pS2, hTERT and HOTAIR promoters at the ERE/eNOS peaks. Interestingly, upon treatment with17β-estradiol HOTAIR recruitment to chromatin increased significantly while that of MALAT1 was reduced, suggesting an opposite regulation and function for these lncRNAs. Similar results were obtained in cells and in an ex vivo prostate organotypic slice cultures. Overall, our data provide evidence of a crosstalk between lncRNAs, estrogens and estrogen receptors in prostate cancer with important consequences on gene expression regulation.

AIM: To investigate the associations of different types of pre-S deletions with hepatitis B virus (HBV) genotypes.
METHODS: The sequences of the pre-S region, basal core promoter (BCP) mutation, and precore (PC) mutation were examined through direct DNA sequencing or clonal analysis and sequencing in 273 HBV carriers, namely 55 asymptomatic carriers, 55 carriers with chronic hepatitis (CH), 55 with liver cirrhosis (LC), 53 with liver cirrhotic hepatocellular carcinoma (LC-HCC), and 55 with noncirrhotic HCC. A total of 126 HBV carriers (46.2%) harbored pre-S deletions. The DNA sequences of pre-S deletion mutants from 43 age-matched genotype B (HBV/B)-infected carriers and 43 age-matched genotype C (HBV/C)-infected carriers were further examined, aligned, and compared.
RESULTS: No significant difference was observed in the mean age distribution (P = 0.464), male sex (P = 0.805), viral load (P = 0.635), or BCP mutation (P = 0.117) between the HBV/B and HBV/C groups. However, the rate of PC mutation was significantly higher in the HBV/B-infected carriers than in the HBV/C-infected carriers (P = 0.003). Both genotypes exhibited a high rate of deletion in the C-terminal half of the pre-S1 region and N-terminus of the pre-S2 region (86.0% and 79.1% in the HBV/B group; 69.8% and 72.1% in the HBV/C group, respectively). Epitope mapping showed that deletion in several epitope sites was frequent in both genotypes, particularly pS1-BT and pS2-B2. Conversely, the rate of pS2-B1 deletion was significantly higher in the HBV/B group (72.1% vs 37.2%, P = 0.002), and the rate of pS2-T deletion was significantly higher in the HBV/C group (48.8% vs 25.6%, P = 0.044). Functional mapping showed that the rate of deletion in three functional sites (the nucleocapsid binding site, start codon of M, and site for viral secretion) located in the N-terminus of the pre-S2 region was significantly higher in the HBV/B group (P < 0.05). One type of N-terminus pre-S1 deletion mutant with deletion of the start codon of the L protein was frequently observed in the HBV/C group (20.9% vs 9.3%, P = 0.228), particularly in the LC patients (42.9% vs 12.5%). Different patterns of pre-S deletions were also found between the HBV/B and HBV/C groups according to different clinical outcomes. In CH patients, deletion in the site for polymerized human serum albumin was more frequent in the HBV/B group (88.9% vs 36.4%, P = 0.028). In the LC-HCC patients, the rate of deletion in the pre-S2 region was significantly higher in the HBV/B group than in the HBV/C group (P < 0.05).
CONCLUSION: HBV/B- and HBV/C-infected carriers exhibit different patterns of pre-S deletion, which may be associated with the progression of liver diseases.

A body of epidemiological evidence implicates exposure to endocrine disrupting chemicals (EDCs) with increased susceptibility to breast cancer. To evaluate the physiological effects of a suspected EDC in vivo, we exposed MCF-7 breast cancer cells and a patient-derived xenograft (PDX, estrogen receptor positive) to physiological levels of methylparaben (mePB), which is commonly used in personal care products as a preservative. mePB pellets (4.4 μg per day) led to increased tumor size of MCF-7 xenografts and ER

Endometrial cancers expressing estrogen and progesterone receptors respond to hormonal therapy. The disappearance of steroid hormone receptor expression is common in patients with recurrent disease, ultimately hampering the clinical utility of hormonal therapy. Here, we demonstrate for the first time that nucleophosmin (NPM1/B23) suppression can restore the expression of estrogen receptor α (ESR1/ERα) in endometrial cancer cells. Mechanistically, B23 and activator protein-2γ (TFAP2C/AP2γ) form a complex that acts as a transcriptional repressor of ERα. Our results indicate that B23 or AP2γ knockdown can restore ERα levels and activate ERα-regulated genes (e.g., cathepsin D, EBAG9, and TFF1/pS2). Moreover, AP2γ knockdown in a xenograft model sensitizes endometrial cancer cells to megesterol acetate through the upregulation of ERα expression. An increased immunohistochemical expression of AP2γ is an adverse prognostic factor in endometrial cancer. In summary, B23 and AP2γ may act in combination to suppress ERα expression in endometrial cancer cells. The inhibition of B23 or AP2γ can restore ERα expression and can serve as a potential strategy for sensitizing hormone-refractory endometrial cancers to endocrine therapy.

The estrogen-related receptor α (ERRα) is an orphan nuclear receptor that plays a primary role in the regulation of cellular energy homeostasis and osteogenesis. It is reported that ERRα is widely expressed in a range of tissues and accumulating evidence has supported that the high expression of ERRα correlates with poor prognosis of various human malignancies, including breast, endometrium, colon, prostate and ovary cancers. Herein is described the discovery of a novel selective inverse agonist (HSP1604) of ERRα, but not of ERRβ and ERRγ, as determined using transient transfection luciferase reporter assay and a time-resolved fluorescence resonance energy transfer (TR-FRET) co-activator assay. HSP1604 potently inhibits ERRα transcriptional activity with IC50=1.47±0.17μM in cell-based luciferase reporter assay and also decreases the protein level of ERRα and the mRNA levels of its downstream target genes such as pyruvate dehydrogenase kinase 4 (PDK4), pS2 and osteopontin. HSP1604 has also suppressed the proliferation of different human cancer cell lines and the migration of breast cancer cells with high expression of ERRα. Representative in vivo results show that HSP1604 suppresses the growth of human breast cancer xenograft in nude mice as doses at 30mg/kg or 100mg/kg administered every other day during 28-day period. HSP1604 thus has the potential both as a new agent to inhibit the growth of tumors and as a chemical probe of ERRα biology.

SCOPE: Obese and overweight women are at high risk of developing endometrial cancer; indeed, many of endometrial cancer patients are obese. The increased number and size of adipocytes due to obesity elevate levels of circulating estrogens that stimulate cell proliferation in the endometrium. However, black raspberries are a promising approach to preventing endometrial cancer.
METHODS AND RESULTS: We examined 17 black raspberry constituents and metabolites (10 μM or 10 μg/mL, 48 h) for their ability to prevent endometrial cancer cells from proliferating. Urolithin A (UA) was most able to suppress proliferation in a time- and dose-dependent manner (p < 0.05). It arrested the G2/M phase of the cell cycle by upregulating cyclin-B1, cyclin-E2, p21, phospho-cdc2, and CDC25B. UA also acted as an estrogen agonist by modulating estrogen receptor-α (ERα) dependent gene expression in ER-positive endometrial cancer cells. UA enhanced the expression of ERβ, PGR, pS2, GREB1 while inhibiting the expression of ERα and GRIP1. Coincubating UA-treated cells with the estrogen antagonist ICI182,780 abolished UA's estrogenic effects. Knocking down ERα suppressed PGR, pS2, and GREB gene expression but increased GRIP1 expression. Thus, UA's actions appear to be mediated through ERα.
CONCLUSION: This study suggests that UA modulates ERα-dependent gene expression, thereby inhibiting endometrial cancer proliferation.

Retinoic acid, the bioactive metabolite of beta-carotene or vitamin A, plays a pleiotropic, multifunctional role in vertebrate development. Studies in rodents revealed that a diet deficient in vitamin A results in a complex neonatal syndrome (the VAD syndrome), manifested in many organs. In humans, the function of retinoic acid (RA) extends into adulthood, where it has important roles in fertility, vision, and suppression of neoplastic growth. In recent years, it has also been suggested that retinoic acid might potentially act as a therapeutically relevant drug in attenuating or even preventing neurodegenerative diseases such as Alzheimer's disease (AD). Here, we report that VAD leads to an increase in A-beta peptide levels while only minor effects were observed on expression levels of the amyloid precursor protein (APP) processing proteinases in wild type mice. In line with these findings, rescue of hypovitaminosis reduced A-beta amount to baseline and induced sApp-alpha secretion in combination with an increase of alpha-secretase Adam10. By comparing retinoic acid treatment starting from a full nutrition status and a "VAD" situation in human neuroblastoma cells, we show that while intensities of differential gene expression were higher in replenished cells, a large overlap in AD-related, regulated genes was observed. Our data suggest that hypovitaminosis A can contribute to onset or progression of AD by increasing synthesis of A-beta peptides and that several AD-related genes such as ADAM10 or BDNF are regulated by retinoic acid. We suggest that dietary supplementation with retinoic acid derivatives is likely to have a beneficial effect on AD-pathology in individuals with hypovitaminosis and patients with normal vitamin A status.

Aberrant estrogen receptor-α (ERα) signaling is recognized as a major contributor to the development of breast cancer. However, the molecular mechanism underlying the regulation of ERα in breast cancer is still inconclusive. In this study, we showed that the transcription factor 21 (TCF21) interacted with ERα, and repressed its transcriptional activity in a HDACs-dependent manner. We also showed that TCF21 could be sumoylated by the small ubiquitin-like modifier SUMO1, and this modification could be reversed by SENP1. Sumoylation of TCF21 occurred at lysine residue 24 (K24). Substitution of K24 with arginine resulted in complete abolishment of sumoylation. Sumoylation stabilized TCF21, but did not affect its subcellular localization. Sumoylation of TCF21 also enhanced its interaction with HDAC1/2 without affecting its interaction with ERα. Moreover, sumoylation of TCF21 promoted its repression of ERα transcriptional activity, and increased the recruitment of HDAC1/2 to the pS2 promoter. Consistent with these observations, sumoylation of TCF21 could inhibit the growth of ERα-positive breast cancer cells and decreased the proportion of S-phase cells in the cell cycle. These findings suggested that TCF21 might act as a negative regulator of ERα, and its sumoylation inhibited the transcriptional activity of ERα through promoting the recruitment of HDAC1/2.

Acquisition of tamoxifen resistance (TR) during anti-estrogenic therapy using tamoxifen is a major obstacle in the treatment of estrogen receptor (ER)-positive breast cancer. As a biguanide derivative, metformin is commonly used to treat type II diabetes. It has recently emerged as a potential anticancer agent. The objective of the present study was to investigate the anticancer activity of metformin in relation to ERα expression and its signaling pathway in ERα-positive MCF-7 and MDA-MB-361 breast cancer cells as well as TR MCF-7 breast cancer cells. Metformin inhibited both protein and mRNA levels of ERα in the presence or absence of estrogen (E2) in the MCF-7, TR MCF-7 and MDA-MB-361 cells. Metformin repressed E2-inducible estrogen response element (ERE) luciferase activity, protein levels and mRNA levels of E2/ERα-regulated genes [including c-Myc, cyclin D1, progesterone receptor (PR) and pS2] to a greater degree than tamoxifen, resulting in inhibition of cell proliferation of MCF-7, TR MCF-7 and MDA-MB-361 cells. Collectively, our results suggest that one of the anticancer mechanisms of metformin could be attributable to the repression of expression and transcriptional activity of ERα. Metformin may be a good therapeutic agent for treating ERα-positive breast cancer by inhibiting the expression and function of ERα. In addition, metformin may be useful to treat tamoxifen-resistant breast cancer.

The direct relationship between obesity and breast cancer has been elucidated recently with the identification of a cholesterol derivative 27-hydroxycholesterol (27HC), an endogenous SERM that can act through estrogen receptor (ER)-mediated mechanisms. Our recent research shed light on the possible SERM-like property of methanol extract of pericarp of pomegranate (PME) by using human breast (MCF-7, MDA-MB-231), endometrial (HEC-1A), cervical (SiHa, HeLa), ovarian (SKOV3) cancer cell lines, normal breast fibroblasts (MCF-10A) and also by in vivo models (ovariectomized Swiss albino mice). Our findings demonstrated that PME binds to ER and downregulates the Estrogen response elements (ERE)-mediated transcription in breast cancer cells without being agonistic in the uterine endometrium and has cardioprotective effects comparable to that of 17-β-estradiol. This preliminary work indicates the ability of PME to antagonize the activity of 27HC. We hypothesize that PME can compete with 27HC for ERα and reduce 27HC-induced proliferation of MCF-7 cells. Relevant estrogen-regulated genes such as pS2, PR and ERα were checked to evaluate the ability of PME to abrogate 27HC-induced genes. This study is significant, being the first report describing that bioactive components of the methanolic extract of pericarp of PME, a proven SERM could plausibly compete for 27HC.

INTRODUCTION: Patients with advanced-stage non-small cell lung cancer (NSCLC) and borderline performance status (performance status 2 [PS2]) are often excluded from clinical trials and platinum-based therapy. In light of the potential role for serum proteomics in predicting the benefit of erlotinib beyond that of epidermal growth factor receptor gene (EGFR) mutational status, we conducted a trial in which the Veristrat proteomics assay was used for data enrichment when selecting a cohort of patients with NSCLC and PS2 to receive erlotinib with and without chemotherapy.
METHODS: Patients with metastatic NSCLC, PS2, acceptable end-organ function, and Veristrat-good status were randomly assigned to receive either 150 mg of erlotinib orally daily (arm 1) or 150 mg of erlotinib orally daily on days 2 through16 plus four cycles of carboplatin (area under the curve = 5 on day 1) and paclitaxel (200 mg/m(2) intravenously on day 1) followed by 150 mg of erlotinib orally (arm 2). The arm 2 agents were pharmacodynamically separated to mitigate potential antagonism. The arm with superior observed median progression-free survival (PFS) would be selected for further evaluation, but only if PFS lasted for at least 3 months.
RESULTS: The trial terminated before the planned accrual of 98 patients for regulatory reasons. A total of 156 patients were screened. Of the 83 (59%) who were classified as Veristrat good, 59 met the trial eligibility criteria and were randomly assigned to one of two arms (33 patients in arm 1 and 26 in arm 2). The patients in arm 2 patients had a higher response rate (23% versus 6%, p = 0.06), disease control rate (77% versus 41%, p = 0.0046), median PFS (4.6 versus 1.6 months, p = 0.06), and median overall survival (11 versus 6 months, p = 0.27). Treatment-related grade 4 adverse events were seen in two patients in arm 1 (thrombosis and hypomagnesemia) and in five patients in arm 2 (neutropenia in five, febrile neutropenia in one, and leukopenia in one).
CONCLUSIONS: In a proteomics-enriched cohort of patients with NSCLC and PS2, pharmacodynamically separated erlotinib plus chemotherapy had better efficacy than did erlotinib alone and surpassed the protocol-specified benchmark of PFS of at least 3 months required for further study.

Hereditary, hormonal, and behavioral factors contribute to the development of breast cancer. Alcohol consumption is a modifiable behavior that is linked to increased breast cancer risks and is associated with the development of hormone-dependent breast cancers as well as disease progression and recurrence following endocrine treatment. In this study we examined the molecular mechanisms of action of alcohol by applying molecular, genetic, and genomic approaches in characterizing its effects on estrogen receptor (ER)-positive breast cancer cells. Treatments with alcohol promoted cell proliferation, increased growth factor signaling, and up-regulated the transcription of the ER target gene GREB1 but not the canonical target TFF1/pS2. Microarray analysis following alcohol treatment identified a large number of alcohol-responsive genes, including those which function in apoptotic and cell proliferation pathways. Furthermore, expression profiles of the responsive gene sets in tumors were strongly associated with clinical outcomes in patients who received endocrine therapy. Correspondingly, alcohol treatment attenuated the anti-proliferative effects of the endocrine therapeutic drug tamoxifen in ER-positive breast cancer cells. To determine the contribution and functions of responsive genes, their differential expression in tumors were assessed between outcome groups. The proto-oncogene BRAF was identified as a novel alcohol- and estrogen-induced gene that showed higher expression in patients with poor outcomes. Knock-down of BRAF, moreover, prevented the proliferation of breast cancer cells. These findings not only highlight the mechanistic basis of the effects of alcohol on breast cancer cells and increased risks for disease incidents and recurrence, but may facilitate the discovery and characterization of novel oncogenic pathways and markers in breast cancer research and therapeutics.

Plants of the genus Taraxacum, commonly known as dandelions, are used to treat breast cancer in traditional folk medicine. However, their use has mainly been based on empirical findings without sufficient scientific evidence. Therefore, we hypothesized that dandelions would behave as a Selective estrogen receptor modulator (SERM) and be effective as hormone replacement therapy (HRT) in the postmenopausal women. In the present study, in vitro assay systems, including cell proliferation assay, reporter gene assay, and RT-PCR to evaluate the mRNA expression of estrogen-related genes (pS2 and progesterone receptor, PR), were performed in human breast cancer cells. Dandelion ethanol extract (DEE) significantly increased cell proliferation and estrogen response element (ERE)-driven luciferase activity. DEE significantly induced the expression of estrogen related genes such as pS2 and PR, which was inhibited by tamoxifen at 1 μmol·L(-1). These results indicated that DEE could induce estrogenic activities mediated by a classical estrogen receptor pathway. In addition, immature rat uterotrophic assay was carried out to identify estrogenic activity of DEE in vivo. The lowest concentration of DEE slightly increased the uterine wet weight, but there was no significant effect with the highest concentration of DEE. The results demonstrate the potential estrogenic activities of DEE, providing scientific evidence supporting their use in traditional medicine.

Estrogen exerts its physiological and pathological functions through two estrogen receptors (ERs), ERα and ERβ, which act as transcription factors. Coregulators, including coactivators and corepressors, have been shown to be crucial for regulation of ER transcriptional activity. Although many coregulators have been identified to regulate activities of ERs, novel coregulators are still needed to be investigated. Here, we show that human methyltransferase-like 17 (METTL17), whose function is unknown, physically interacts with ERα and ERβ, and functionally acts as a coactivator for ERs. METTL17 interacts with ER in vitro and in yeast and mammalian cells. Activation function-1 (AF1) and AF2 domains of ERs are responsible for the interaction between METTL17 and ERs. Knockdown of METTL17 reduces transcriptional activities of ERα and ERβ in breast cancer cells, whereas METTL17 overexpression increases ERα and ERβ transcriptional activities. Inhibition of METTL17 expression decreases mRNA and protein levels of ER target genes, including PR, cathepsin D, and pS2. Moreover, METTL17 knockdown reduces breast cancer cell growth. These results indicate that METTL17 is a novel coactivator of ERs and may play a role in breast tumorigenesis.

BACKGROUND: Mutations within exons 16 and 17 of the amyloid-β protein precursor (AβPP) gene were the first known causes of early-onset familial Alzheimer's disease (EOFAD). Since the first AβPP mutation was reported, 39 different AβPP variations have been discovered in EOFAD.
OBJECTIVE: We described a novel AβPP M722K mutation found in a Chinese familial Alzheimer's disease pedigree and confirmed its effects on amyloid-β (Aβ) secretion and tau phosphorylation.
METHODS: We performed direct sequencing of exons 16 and 17 of the AβPP gene and coding exons 3-12 of the PSEN1 and PSEN2 genes for genetic analysis. N2a cells were transfected with wild-type AβPP, AβPP constructs harboring the M722K mutation, or AβPP constructs harboring the Swedish mutation to demonstrate the effects of the AβPP M722K mutation on Aβ secretion and tau phosphorylation.
RESULTS: Different phenotypes of patients carrying the AβPP M722K mutation maybe were related to different apolipoprotein E genotypes. The expression of AβPP M722K in mouse neuroblastoma N2a cells induced a 1.7-fold increased ratio of Aβ 42 to Aβ 40 without changes in sAβPPα and sAβPPβ. Tau phosphorylation at the AT8 sites was also increased.
CONCLUSION: Maybe the AβPP M722K mutation contributed to the cause of EOFAD in this Chinese pedigree mediated by increased Aβ 42/Aβ 40. Further studies should be conducted to validate the pathogenicity of AβPP M722K and the interactions among γ-secretase, APOE, and AβPP.